Fig. 5.

Characterisation of CB-MSC osteogenic differentiation under normoglycaemic and hyperglycaemic conditions. a Mineral deposition, as visualised by Alizarin Red staining, by CB-MSCs cultured for 28 days in osteoinductive and basal (control) medium. Hyperglycaemia inhibited CB-MSC osteogenic differentiation at PD15, PD100 and PD200, but not at PD50. b Quantification of Alizarin red staining by CB-MSCs cultured for 28 days in osteoinductive medium, confirming significantly reduced staining at PD15, PD100 and PD200 under hyperglycaemic conditions, but not at PD50. Assessment of c early (osterix) and d late (OCN) osteogenic marker expression by CB-MSCs under normoglycaemic and hyperglycaemic conditions, by Q-PCR. CB-MSCs at PD15 under normoglycaemic conditions exhibited significant increased osterix expression at day 2, compared to PD50, PD100 and PD200. Hyperglycaemic conditions significantly reduced osterix expression at day 2. CB-MSCs at PD15 exhibited significantly elevated OCN expression under hyperglycaemic conditions at day 21. Although OCN expression declined by day 28, significantly elevated OCN expression was shown at PD15 under normoglycaemic conditions. OCN expression was severely impaired at PD50 under both normal and high glucose conditions. Hyperglycaemic conditions exerted no significant effects on OCN expression at PD100 and PD200, although significantly increased expression was evident at PD100 under normal glucose conditions, at day 28. Significance between CB-MSC populations are shown, ***p < 0.001, *p < 0.05